using Knot.Modules.Auth.Domain;
using Knot.Modules.Auth.Application.Abstractions;
using Knot.Shared.Kernel;
using Knot.Modules.Auth.Application.Users.Auth;
using BCrypt.Net;

namespace Knot.Modules.Auth.Application.Users.Login;

/// <summary>
/// Команда для входа пользователя. Возвращает AuthResponseDto.
/// </summary>
public sealed record LoginUserCommand(string Username, string Password) : ICommand<AuthResponseDto>;

public sealed class LoginUserCommandHandler : ICommandHandler<LoginUserCommand, AuthResponseDto>
{
    private readonly IUserRepository _userRepository;
    private readonly IJwtTokenProvider _tokenProvider;

    public LoginUserCommandHandler(IUserRepository userRepository, IJwtTokenProvider tokenProvider)
    {
        _userRepository = userRepository;
        _tokenProvider = tokenProvider;
    }

    public async Task<Result<AuthResponseDto>> Handle(LoginUserCommand request, CancellationToken cancellationToken)
    {
        var user = await _userRepository.GetByUsernameAsync(request.Username, cancellationToken);

        if (user is null || !BCrypt.Net.BCrypt.Verify(request.Password, user.PasswordHash))
        {
            return Result.Failure<AuthResponseDto>(AuthErrors.IdentityInvalidCredentials);
        }

        string token = _tokenProvider.Generate(user);

        return Result.Success(new AuthResponseDto(
            token,
            new AuthUserDto(
                user.Id,
                user.Username,
                user.DisplayName,
                user.Email,
                user.Bio,
                user.Avatar,
                user.Birthday,
                true, // IsOnline (placeholder)
                user.CreatedAt
            )
        ));
    }
}